What makes that OK?

So, I have this teacher. A teacher who works hard, is always well prepared, and is enthusiastic about his subject almost to the point of over-enthusiasm.
And then there are these students. Students who may or may not do the readings and are obviously not invested in the class. And what do they do? They sit in the classroom and for the majority of the class time proceed to make faces at the rest of the class in order to make it BLINDINGLY obvious that they think the professor is an idiot. Well, to those people, I have only this to say:

You clearly do not deserve the effort that he is putting into this class to at least TRY and make it interesting. Yes, the subject matter is boring, but that's a curriculum fault. It's a requirement for your major, so SUCK IT UP and stop acting like you have better places to be. At that time, odds are you really don't. If you stopped looking for the slightest faults in every word of every sentence you may actually find yourself ::gasp:: learning something! What a novel idea, right?

I'll never understand how people can do that. Yes, I've had some teachers in my life that I definitely did not agree with. I even had some teachers that I thought perhaps should not be teaching. But, they are STILL your teacher, and with that title comes respect. Respect that means they should not get up in front of the classroom and have to worry about who is making snide remarks and annoyed faces during class.

That's my rant. I'll edit it when I stop being so mad.